Title: Conditional logics and labelled proof systems (an introduction)

Abstract:

Conditional logics, as introduced by David Lewis in 1973, enrich the language of classical propositional logic with a two-places modal operator, the conditional, suitable to represent fine-grained notions of conditionality. After introducing conditional logics and their semantics, that I will define in terms of neighborhood models, I will illustrate how to define labelled proof systems for a large family of conditional logics. Labelled proof systems, first introduced for modal logics, enrich the language of Gentzen-style sequent calculus with semantic information. I will discuss the main properties of labelled proof systems, showing that, similarly to the case of modal logics, labelled calculi offer great flexibility in the definition of analytic proof system for conditional logics.

This talk is introductory and does not presuppose any knowledge of conditional logics or labelled proof systems. The material presented comes from joint work with Sara Negri and Nicola Olivetti.

The seminar will held online on March 5th, at 14:30 (Rome time) on the Microsoft Teams platform, here.